.content {
    width: 100%;
    background-color: #e7e4d5;
}

.book_box {
    width: 1100px;
    margin: 20px auto 0 auto;
    background-color: #f6f4ec;
    text-align: center;
    padding: 50px 50px 0 50px;
    transition: all 1s ease 0s;
}

.btn {
    display: inline-block;
    width: 1000px;
    height: 40px;
    margin-bottom: 10px;
    /*background-color: pink;*/
}

.next {
    height: 40px;
    padding-top: 10px;
    border-bottom: 1px solid #ccc;
}

.next a {
    line-height: 40px;
    color: #151515;
}

.btn a:hover,
.next a:hover,
.next_footer a:hover {
    color: orange;
}

.book {
    font-size: 25px;
}

.book p {
    font-size: 19pt;
    color: #555;
    text-indent: 2em;
    line-height: 2em;
    margin: 1em 0;
    /*实现两端文本对齐*/
    text-align: justify;
    transition: all 1s ease 0s;
}

.next_footer {
    height: 80px;
    border-top: 1px solid #ccc;
}

.btn a,
.next_footer a {
    display: inline-block;
    line-height: 40px;
    padding: 0 20px;
    margin: 20px 20px;
    background-color: #fff;
    border: 1px solid #ccc;
    color: #151515;
}

.js_box {
    width: 300px;
    height: 50px;
    float: right;
}

.js_box select {
    width: 50px;
    height: 24px;
}